Correct spelling


Correct spelling, explanation: this is the correct form because the word comes from seize with a suffix. This is why we spell it seizure not siezure. Seize comes from Old French seisir, hence the spelling. The correct form, thus, is seizure.

Definition of seizure:
noun, the act of taking something by force or legally; also an attack of an illness or other condition (this meaning occurred in the 18th century).
These regulations are considered a seizure of goods.
The nurses will attend the course on how to react in case of bleeding, attack, or seizure.

Incorrect spelling


Incorrect spelling, explanation: siezure is incorrect because the word seizure is a noun from the noun seize. As you can see the spelling remains, and the mistake probably occurs due to pronunciation. The correct spelling is seizure.